1. Field of the Invention
The present invention relates to a scan driver, a display device having the scan driver, and a method of driving the display device. More particularly, the present invention relates to a scan driver enhancing display quality of a display device, a display device having the scan driver, and a method of driving the display device.
2. Description of the Related Art
A display device converts electric signals processed by an information process device into an image. Examples of the display device include a liquid crystal display (“LCD”) device, an organic light-emitting diode (“OLED”) device, a plasma display panel (“PDP”), etc.
The LCD device has many merits, and is therefore used in various fields. The LCD device includes a plurality of gate lines extended along a first direction of an array substrate, a plurality of source lines extended along a second direction of the array substrate that is substantially perpendicular to the first direction, and a plurality of liquid crystal capacitors each electrically connected to one of the gate lines and one of the source lines.
The gate lines are activated in sequence. When one of the gate lines is activated, a data voltage is applied to the liquid crystal capacitors through the source lines, so that the liquid crystal capacitors are electrically charged. When the liquid crystal capacitors are electrically charged, electric fields are generated between a pixel electrode on the array substrate and a common electrode, disposed on an opposite substrate, defining the liquid crystal capacitor. When electric fields are generated between the pixel electrode and the common electrode, an arrangement of liquid crystal molecules of a liquid crystal layer disposed between the pixel electrode and the common electrode is changed. As a result, an optical transmittance of the liquid crystal layer is changed to display an image.
A time period during which first through last gate lines are activated is referred to as one frame.
As a size of the display device increases, and a resolution of the display device is enhanced, a number of gate lines increases. However, one frame is fixed. As a result, a time for activating each gate line decreases.
The data voltage is applied to the liquid crystal capacitor while the gate line is activated. Thus, when the time for activating the gate line decreases, a time for electrically charging the liquid crystal capacitor also decreases, so that a voltage of the liquid crystal capacitor may not arrive at the data voltage. In other words, a charging rate of the liquid crystal capacitor is lowered.
Furthermore, when a driving frequency is raised in order to reduce afterimage effects, the time for electrically charging the liquid crystal capacitor is further reduced.